Glossary
Rollback plan
What to do when the update fails: how to get back to the previous state, how long that takes, and who decides it is time to stop and revert.
Also calledback-out plan · reversion plan
The other half of every maintenance window. A rollback plan answers three questions: how the system is returned to its previous state, how long that takes, and who is authorised to decide to go there.
The third one is the one that gets forgotten. At three in the morning, when the install is not finishing, somebody has to be authorised to say stop. Without a decision point agreed in advance, the window stretches until users arrive.
What belongs in the checklist
- A backup or snapshot taken before installation, and verified.
- The decision time — the point at which reverting begins.
- Who approves the revert, and who is told once it is done.